*STRUREL* offers an interface to *Matlab*: You can evaluate *Matlab* *functions* or *Matlab* *scripts* within a limit-state function call.

The initial start of the *Matlab* *engine* takes a bit. Therefore, to be able to evaluate your *Matlab*-based limit-state function calls efficiently, we keep the *Matlab* *engine* running in the background. You need to be aware of this behavior, if you work with external *Matlab* scripts: When you change the content of your script, you need to manually restart the *Matlab* *engine*. Otherwise, the *Matlab* *engine* will not take the changes you made into account.

The simplest way to force a re-load of the *engine* is to close the *Matlab* *engine* actively. Add the following code in the ‘*Symbolic Expressions*‘ tab of *STRUREL*:

`FLIM(2)=matlabf("%quit")`

Now, you simply have to evaluate this limit-state function each time you want to enforce a re-start of the *Matlab* *engine*.